Electric fuse.



-=PAT ENTED JAN'.

F( MACKINTOSH.

B'LEGTRIC .FUSB. APPLIGATION PILED SEPT. 29,1904.

WfLnesses;

amy.

I FREDERTCKMAGKINTOSH, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELUTRI COltIl-"JUQY,` A COR PORATION OF NEW YORK.

ELECTRIC FUSE.

Specfication of Letters Patenta.

' Patented Jan. 21, mos.

i To all 'whom tt may concer'n:

Beit known that I, FREDERICK MACKN- TOSH, a citizen of the United States, rsiding at Schenectady, County of Seleie'etal y; State of New York, have invented certain new and useful Improvements `in Electric Fuses, of which the following is a specificaton.

My nventon relates to fuses for electric circuits, and its object is to provide a novelform' of fuse adapted to open electrc circuits of high tension 'efficiently and reliably. I

It is wellknown'in the art that the are form'ed on opening a circuit may be blown out almost instantaneously by a blast et air.

v the fus'e metal causes a rush of 'air through that portion of the 'fuse which hes blown, thereby 'quickly extnguishing the are that is formed. y

More specifically considered, ny invention consists in enploying a tuhular fuse which forms a portion of the containing walls of an inclosed chamber, so that when a portion .of the fuse blows a rush of air into or out of the tube is p'roduced,` according as the Vinclosed chanber ,is formed outside of or within the tube.

Another feature of my invention consists in supplementing the pressure produced by the -vo compressed air, whereby the rush of air is increased and the are more effectually extin'- e guished.

by the conipressed air Another feature of my ;inventien consists in forniing the tubular fuse with thickened walls for the greater portion of its length; so that its' strength is thereby increased and. it is enabled to stand a greater pressure. i

Another feature of my invention consists in providing a whistle arranged to be blewn assing 'froni *the *source outward through t e tube, se as to give warning to the attendant that the'fuse has blown.

Other features of my invention will appear from the following specification and accompan ing drawing; which 'shows a crosssectonal view.of a fuse arr nged n accordance with my invention.

- fuse blows.

atilization of the fuse bye source' of' In the drawing, A represents a cylindrical casng which is hned with or composed oi nsulating material, as shown. This casing is provided :it each end with a head .or ca (L.

B represents 'a tubulzr i'use whicl .extends through the casing, and the ende oi' which are expanded to form with the heads c substantially a ir-tight joints. lt will be seen that the 'fuse is redueed in 'thickhess near the center, as i'ndicated at l). With this arrangement, the greater part of the fute desired pressure.

C represents anoutlet froni thecasing hy means of which connection may hi made to a source of eoinpressed air.

D D represent whistles which 2.1 re placed in the ends of the tubula-r fuse. I The operation is as follows: Vhen an ove rload comes upon the circuit in whichthe fuse is connected, the reduced central portion 'of the fuse is blown, and the pressure produeed by volatilization, assisted by the pressure from the auxliary source, produces a rush of air from the charnber outwardly through the tubular fuse and eectually, extingiishes the are which is forned when the Since the rush of air must always occur at the pointat which the .i'use melts, it always occ'urs at the proper point for extinguishing the are. After the fu'se is blown, 'the' whistles D D, through which air from the auxliary source is still passing, give continuous warning to the' attendant that the fuse is blown. Obviously, the location of these'whistles may be changed if desired.

. It is not 'essential to myinvention that acylin'drical form of fuse be employed, nor is it necessary that the hise should be tubuler;

although Suche form is especially adaptedv for e compact structure. lt is only essential that the fuse itself should 'form a portion of the inclosed walls of a substantielly air-tight chamber, so that the point at which the fuse nelts will be'the pointat which the flow of air from the chenber will be. produced.

may be made amply strong to withstand the Accordihgly, I do not desire' to limit myself to' the particular consti'uction V and arrangement ofiparts shown, .butaim in the appended claims to cover all inodificatio s which are within the scope of my invention. .What I 'claim as new and desire to 'secure by Letters Patent of the United States, is:

1. In an e1ectriccut-.out, a substantelly air-tight chanber, and a fuse'forniing a portion of the inclosing walls thereof and exair-fight cha-mbet', and a tubular fuse exposed on its side to atnosphere.

2.-In an electriccut-out, a substantially air-fight chanber, a fuse formin a portion of the inclosing alis thereof, an means for connecting said chamber to a source of gaseous pressure.

. 3. In an eiectric cut-out, a substantially air-tight chaniber, and a tubular fuse extending through said chanber and forming a portion of the inclosing walls thereof, the 1nner passage of said fuse being open to atmosphere.

4. In an electric cut-out, a substantially air-tight chamber, a tubular fuse extending through said chainber, and a connection from said chamber to a source of gaseous pressure. p

5. In' an electric cut-out, a substantially air-'Light chamber, a tubular fuse therein having its inner passage connected to atmosphere, and a connection from said chamberto a source of gaseous pressure.

6-. In an electric cut-out, a piece of fuse metal forming a portion of 'an electric circuit and normally exposed on one side to a source of gaseous pressure and on the other to atmosphere.

7. In an electrc cut-out, a substantially tending through said chanber and forning a portion of the'inclosing walls ,thereof, the inner passage of said fuse being open to atmosphere and a central portion of the fuse being reduced in thickness.

8. In an electric cut-out, a substantially air-tight chamber, a tubuhr fuse extendng through said chamber and forniing a portion of the inclosing walls thereof, the inner passage of said fuse being open to atmosphere and a central portion of the fuse being reduced in thickness, and means for connecting said chanber to a, source of gaseous pressure.

9. In an electric cut-out, a substantially air-tight chamber, a tubular fuse extending through said chamber, a connection between said chanber and a source of compressed air, and a whistle adapted and arranged to be blown by the passage of air from said source through said tube.

In Witness Whereof I have hereunto set my hand this 28th day of September, 1904.

FREDERICK MACKINTOSH. 

